Is it possible, that once all the bicoins are minted, the code is designed in such a way, that the entire ledger or stack of cards, comes tubling down and all cryptos are deleted?
closed as primarily opinion-based by Pieter Wuille, Andrew Chow♦ Apr 16 '18 at 3:24
Many good questions generate some degree of opinion based on expert experience, but answers to this question will tend to be almost entirely based on opinions, rather than facts, references, or specific expertise. If this question can be reworded to fit the rules in the help center, please edit the question.
No, that's not possible. The people behind the code are invested in the success of bitcoin.
If they designed it to crash to nothing, even way off in the future (around 2140), their motives would be pulled in to question and deflate confidence in bitcoin today.
Also, remember the code is public and someone would have spotted such a deliberate undermining of the coin.